Implant could help the blind to see again

Gemma Murray

A life-changing implant, which could help the blind see again, has been developed by scientists.

Around one in 30 people in the UK have some sight loss around around 360,000 are registered as blind or partially sighted.

But a new implant, which transmits visual signals to the brain could offer new hope to thousands.

Researchers studied patients with Retinitis Pigmentosa (RP), a hereditary illness that causes sufferers' vision to gradually deteriorate, until they are completely blind.

Scientists assessed the perceptual and brain responses of a the patients, before giving each participant a prosthetic implant.

With the help of the implant, six in seven were able to recognise visual stimuli, such as flashes of light.

The implant works by sensing visual signals and sending them to the brain by stimulating axons of retinal ganglion cells.

Using an MRI scanner, the scientists found patients could recognise unusual visual stimuli, such as flashes of light.

They also observed increased brain activity as a result of the implants.

And the more patients practised spotting the flashes of light, the more their brain responded to the light and the more they improved.

The study, published in the journal PLOS Biology, is one of the first to show how a prosthetic device could help the brain "re-learn" how to see, even after years of blindness.

Author Elisa Castaldi, a PhD student at the University of Pisa, Italy, said: "After surgery five out of seven blind RP patients were able to detect high contrast stimuli using the prosthetic implant."

Study author Professor Maria Morrone, also from Pisa, said: "This is, to our knowledge, the first study tracking the neural changes of visual areas in patients after retinal implant, revealing a capacity to respond to restored visual input, even after years of deprivation."